Traveling pneumatic cleaners such as those illustrated, by way of example, in prior U.S. Pat. Nos. 3,304,571; 3,429,745; and 3,437,520 have achieved wide acceptance in the textile industry as accomplishing highly desirable improvements in the operation of the textile machines being cleaned and in the working environment for operators of those machines. As installed for use, such traveling pneumatic cleaners often operate over a plurality of textile machines, along circuits defined by track ways. In designing track way layouts for specific installations, it is frequently desirable to have a specific track way define a closed circuit for travel over a group of textile machines. However, in some installations it is necessary to have a track way layout which is other than a closed loop. Additionally, in closed loop installations it is necessary, from time to time, to prevent a traveling cleaner from passing over a specific textile machine.
In meeting these requirements for the use of traveling cleaners in textile mills, such cleaners have heretofore been provided with reversing arrangements. Typically, electrical power supplied to a tractor motor for the traveling cleaner has been delivered through a multiple pole switch. Switch actuating mechanism has been provided in order that, upon impacting a permanent or temporary bumper, the switch may be changed so as to immediately reverse the direction of rotation of the tractor drive motor.
While traveling pneumatic cleaners which accomplish reversing of the direction of travel in the manner just described have operated quite successfully, it has become apparent that the sudden reversal of the direction of travel of a tractor drive motor imposes electrical and mechanical strains on the traveling pneumatic cleaner drive arrangements. As persons knowledgeable in the design and use of electrical drive arrangements will appreciate, the sudden reversal of the direction of rotation of an electrical motor following impact of the relatively massive traveling cleaner with a bumper stop results in significant electrical current demands and in the imposition of significant mechanical forces on the structure of the cleaner.